Powder or granular material feeding apparatus

ABSTRACT

A powder or granular material feeding apparatus includes a guide cylinder having a plurality of gas suction holes that guides gas in an interior thereof to an outside, a filter provided on a portion of the guide cylinder where the gas suction holes are formed, a gas feed unit configured to feed inert gas, an auger including a revolving shaft positioned in the guide cylinder and a blade provided on the revolving shaft, and an suction device. The revolving shaft includes a gas feed channel configured to guide the inert gas and a gas feed port configured to allow the inert gas to eject therefrom to cause the powder or granular material to contain the inert gas. The suction device sucks the gas in the guiding cylinder to the outside of the guide cylinder.

TECHNICAL FIELD

The present invention relates to a powder or granular material feedingapparatus configured to feed powder or granular materials.

BACKGROUND ART

In the related art, there is a powder or granular material feedingapparatus configured to supply powder or granular materials in the formsof powder, granules, and the like into a storage bag. In this case, thepowder or granular materials are stored in the storage bag with air andsealed in many cases. However, there are the powder or granularmaterials which may be oxidized, altered, or solidified by air afterlong term storage in a sealed storage bag depending on types of thepowder or granular materials. Examples of such powder or granularmaterials include flour, non-fat dry milk powder, toner containing amagnetic material for copying machines, and the like.

Therefore, there is a powder or granular material feeding apparatusconfigured to deaeration (degassing) and store the powder or granularmaterial in a storage bag (Patent Literature 1).

CITED LIST Patent Literature PTL1: JP-A-2011-84311 SUMMARY OF THEINVENTION Technical Problem

However, the powder or granular material feeding apparatus of therelated art has a limitation in enhancing a deaeration ratio, and has alimitation in elongating a quality guarantee period of the powder orgranular materials.

Accordingly, the present invention intends to provide a powder orgranular material feeding apparatus configured to perform deaerationbetween the powder or granular materials, eject an inert gas from theinside of the powder or granular materials toward the outside, and causethe powder or granular materials to contain the inert gas.

Solution to Problem

A powder or granular material feeding apparatus including: a guidecylinder having a plurality of through holes that guides gas in aninterior thereof to an outside formed therethrough and configured toguide a powder or granular material; a filter provided on a portion ofthe guide cylinder where the through holes are formed to allow the gasin the interior of the guide cylinder to flow to the outside via thethrough holes and prevent the powder or granular material in the guidecylinder from leaking from the through holes to the outside; a gas feedunit configured to feed inert gas; an auger including a revolving shaftpositioned in the guide cylinder and configured to rotate, and a bladeprovided on the revolving shaft and configured to transport the powderor granular material by being rotated by the rotation of the revolvingshaft in the guide cylinder, the revolving shaft including a gas guidechannel configured to guide the inert gas supplied by the gas feedportion and a gas feed port configured to allow the inert gas guided bythe gas guide channel to eject therefrom to cause the powder or granularmaterial to contain the inert gas; and a suction device configured tosuck the gas in the guiding cylinder to the outside of the guidecylinder via the through holes and the filter.

Accordingly, the powder or granular material feeding apparatus of thepresent invention causes the powder or granular material to contain theinert gas from the gas feed port of the gas guide channel outward fromthe inside of the powder or granular material while transporting thepowder or granular material by the auger in the guide cylinder, andsucks the gas in the interior of the guide cylinder by the suctiondevice via the through holes and the filter to the outside, so that theinert gas may be filled within the powder or granular material toprevent oxidization and solidification of the powder or granularmaterial and maintain the quality of the powder or granular materialconstant for a long term.

Preferably, the revolving shaft includes a plurality of the gas feedports along the revolving shaft in the axial direction, and the guidecylinder includes a plurality of the through holes along the axialdirection so as to oppose the plurality of the gas feed ports.

Accordingly, the powder or granular material feeding apparatus mayachieve the deaeration of the powder or granular material and filling ofthe inert gas simultaneously and efficiently.

Preferably, the revolving shaft includes the plurality of the gas feedports over the entire length of the revolving shaft in the axialdirection; and the guide cylinder includes the plurality of the throughholes formed over the entire length of the guide cylinder.

Accordingly, the deaeration of the powder or granular material andfilling of the inert gas may be achieved simultaneously and efficientlyeven though the speed of transportation of the powder or granularmaterial is increased.

Preferably, the guide cylinder includes: a gas non-leak portion wherethe through holes are not formed and opposing the gas feed ports; anupper sucking portion having the plurality of the through holes formedtherethrough and formed upstream of the gas non-leak portion in theaxial direction; and a lower sucking portion having the plurality of thethrough holes formed therethrough and formed downstream of the gasnon-leak portion in the axial direction.

Accordingly, the powder or granular material feeding apparatus expelsgas contained in the powder or granular material by the upper suckingunit while transporting the powder or granular material by the auger inthe guide cylinder, cause the powder or granular material to contain theinert gas from the gas feed port in the gas non-leak portion, and sucksthe residual air contained in the powder or granular material and theinert gas by the lower sucking unit. Therefore, oxidization andsolidification of the powder or granular material are prevented and thequality of the powder or granular material may be maintained constantfor a long term.

Preferably, the guide cylinder includes a gas ejection port configuredto eject the inert gas at a distal end thereof.

Accordingly, for example, the air in the storage bag to which the powderor granular material is to be supplied is reduced and, instead, thestorage bag may be filled with the inert gas, so that the powder orgranular material is prevented from containing air when being stored inthe storage bag, and hence the quality guarantee period of the powder orgranular materials may be elongated.

Preferably, the inert gas is nitrogen gas.

Accordingly, oxidation of the powder or granular material can beprevented by nitrogen gas and the quality guarantee period of the powderor granular materials may be elongated.

Also, the powder or granular material is, for example, grain powder.

Accordingly, even though the powder or granular material is the grainpowder which is liable to be solidified easily, solidification of thegrain powder is prevented and the quality guarantee period of the grainpowder may be elongated.

Alternatively, the powder or granular material is, for example, tonerfor image formation.

Accordingly, even though the powder or granular material is toner forimage formation, which is liable to be oxidized easily, oxidization isprevented and the quality guarantee period of the toner for imageformation may be elongated.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic drawing partly in cross section, illustrating anappearance of a powder or granular material feeding apparatus of a firstembodiment of the present invention.

FIG. 2 illustrates a cross section viewed in a direction indicated by anarrow A-A in FIG. 1.

FIG. 3 illustrates a cross section viewed in a direction indicated by anarrow B-B in FIG. 1.

FIGS. 4A and 4B illustrate a cross section viewed in a directionindicated by an arrow C-C in FIG. 2 and FIG. 3, in which FIG. 4A is ageneral view and FIG. 4B is a cross-sectional view of a portion of anegative pressure chamber.

FIG. 5 illustrates a cross section viewed in a direction indicated by anarrow D-D in FIG. 2 and FIG. 3.

FIG. 6 illustrates a cross section viewed in a direction indicated by anarrow E-E in FIG. 2 and FIG. 3.

FIG. 7 is a state drawing of the powder or granular material feedingapparatus before feeding the powder or granular material into a storagebag, and illustrates a cross section viewed in a direction indicated byan arrow D-D in FIG. 2 and FIG. 3.

FIG. 8 is a state drawing of the powder or granular material feedingapparatus while feeding the powder or granular material into a storagebag, and illustrates a cross section viewed in a direction indicated byan arrow C-C in FIG. 2 and FIG. 3.

FIG. 9 is a state drawing of the powder or granular material feedingapparatus immediately after termination of feeding the powder orgranular material into a storage bag, and illustrates a cross sectionviewed in a direction indicated by an arrow E-E in FIG. 2 and FIG. 3.

FIG. 10 is a schematic drawing partly in cross section, illustrating anappearance of a powder or granular material feeding apparatus of asecond embodiment of the present invention.

FIG. 11 illustrates a cross section viewed in a direction indicated byan arrow F-F in FIG. 10.

FIG. 12 illustrates a cross section viewed in a direction indicated byan arrow J-J in FIG. 10.

FIGS. 13A and 13B illustrate a cross section viewed in a directionindicated by an arrow K-K in FIG. 11 and FIG. 12, in which FIG. 13A is ageneral view and FIG. 13B is a cross-sectional view of a portion of anegative pressure chamber.

FIGS. 14A and 14B illustrate a cross section viewed in a directionindicated by an arrow L-L in FIG. 11 and FIG. 12, in which FIG. 14A is ageneral view and FIG. 14B is a cross-sectional view of a portion of thenegative pressure chamber.

FIG. 15 illustrates a cross section viewed in a direction indicated byan arrow M-M in FIG. 11 and FIG. 12.

FIG. 16 illustrates a cross section viewed in a direction indicated byan arrow N-N in FIG. 11 and FIG. 12.

DESCRIPTION OF EMBODIMENTS

Hereinafter, a powder or granular material feeding apparatus of a firstembodiment of the present invention will be described with reference toFIG. 1 to FIG. 9, and a powder or granular material feeding apparatus ofa second embodiment of the present invention will be described withreference to FIG. 10 to FIG. 16.

(Powder or Granular Material Feeding Apparatus of First Embodiment)

Configuration of a powder or granular material feeding apparatus of thefirst embodiment will be described.

As illustrated in FIG. 1, a powder or granular material feedingapparatus 11 is an apparatus configured to feed or fill a powder orgranular material into a storage bag S. Examples of the powder orgranular material include grain powders such as flour, non-fat dry milkpowder, image forming toner containing a magnetic material for copyingmachines, and the like.

The powder or granular material feeding apparatus 11 is provided so asto extend upright on a fixing member 12. The fixing member 12 having asupport post 13 with extending upright thereon, and the support post 13is provided with an elevating shaft 14 so as to be movable upward anddownward. The elevating shaft 14 is configured to move upward anddownward the support post 13 by an elevating mechanism, which is notillustrated, when a handle 15 is rotated.

The elevating shaft 14 includes a hopper 17, and a cylindrical guidecylinder 18 provided via a bracket 16. The hopper 17 stores the powderor granular material therein. A motor, which is not illustrated,configured to rotate an auger (also known as a screw) 19 and a cover 20in which the motor is stored therein are provided on an upper endportion of the elevating shaft 14.

As illustrated in FIGS. 4A and 4B, the auger 19 includes a revolvingshaft 21 positioned in the guide cylinder 18 and configured to rotate,and a blade 22 provided on the revolving shaft 21 and configured torotate in the guide cylinder 18 by the rotation of the revolving shaft21 to convey the powder or granular material. The blade 22 is formedinto a circular shape when viewed from an end portion of the revolvingshaft 21 as illustrated in FIG. 2. The revolving shaft 21 is rotatablysupported by the hopper 17 and the cover 20. The revolving shaft 21penetrates through the cover 20 and the hopper 17, and extends to aposition near a powder or granular material discharge port 18 a of theguide cylinder 18.

A nitrogen feed channel (a gas guide channel) 23 configured to guidenitrogen gas (inert gas) N₂ supplied by a nitrogen gas feeding apparatus(a gas feed unit) 27 is formed along an axial center of the revolvingshaft 21 from an upper end to a substantially lower end of the revolvingshaft 21. The nitrogen feed channel 23 includes a plurality of nitrogenejection ports (gas feed ports) 26 formed radially outward from thenitrogen feed channel 23 as illustrated in FIG. 3, and along an axialdirection of the revolving shaft 21 as illustrated in FIG. 4A. Thenitrogen ejection ports 26 are configured to allow nitrogen gas guidedby the nitrogen feed channel 23 to be ejected out to cause the powder orgranular material to contain the nitrogen gas. As illustrated in FIG. 1,the head portion of the revolving shaft 21 is connected to the nitrogengas feeding apparatus 27 configured to feed the nitrogen gas via arotatable elbow 25 and a nitrogen feed pipe 24.

In FIGS. 4A and 4B, the guide cylinder 18 is formed into a cylindricalshape, and is configured to guide the powder or granular material thatthe auger 19 conveys from the hopper 17 to the storage bag S. The guidecylinder 18 is formed with a plurality of air-gas suction holes (throughholes) 28 configured to guide gas in the interior to the outside. Aplurality of the air-gas suction holes 28 are formed from a portionlower than the hopper 17 to a distal end (lower end in FIG. 4A) of aposition near the powder or granular material discharge port 18 a of theguide cylinder 18. The gas includes air contained in the powder orgranular material and the nitrogen gas ejected from the nitrogenejection ports 26.

A portion of the guide cylinder 18 including the air-gas suction holes28 formed therethrough is provided with a filter 29 formed into acylindrical shape on the outer periphery thereof. The filter 29 isconfigured to allow the gas in the guide cylinder 18 to flow outwardthrough the air-gas suction holes 28, and prevents the powder orgranular material in the guide cylinder 18 from leaking out from theair-gas suction holes 28.

A portion of the guide cylinder 18 including the air-gas suction holes28 formed therethrough is lower in strength. The outer peripheralportion of the cylindrical filter 29 needs to be protected. Therefore, areinforcing cylinder 71 configured to reinforce the guide cylinder 18and protects the outer periphery of the filter 29 is provided on theoutside of the filter 29 so as to interpose the filter 29 between theguide cylinder 18 and the reinforcing cylinder 71. The reinforcingcylinder 71 has a length enough for cover the filter 29. The reinforcingcylinder 71 is also provided with a plurality of air-gas suction holes72 so as to oppose the air-gas suction holes 28 formed in the guidecylinder 18. The air-gas suction holes 72 are also configured to guidethe gas in the interior of the guide cylinder 18 to the outside.

The reinforcing cylinder 71 includes a negative pressure chamber 73formed on the outer periphery thereof. The negative pressure chamber 73includes an outer peripheral cylinder 74, an upper lid 75, and a lowerlid 76. The outer peripheral cylinder 74 is separated from thereinforcing cylinder 71, is mounted on the guide cylinder 18 at an upperportion thereof with a ring-shaped upper lid 75, and mounted at a lowerportion thereof to the powder or granular material discharge port 18 aof the guide cylinder 18 by a ring-shaped lower lid 76. The negativepressure chamber 73 is formed in an area wider than an area in which theair-gas suction holes 28 and 72 are formed. FIG. 4B is a drawingillustrating a positional relationship among the guide cylinder 18, thefilter 29, the reinforcing cylinder 71, and the outer peripheralcylinder 74. The reinforcing cylinder 71 is not necessarily essential aslong as the guide cylinder 18 is reinforced by the outer peripheralcylinder 74.

A gas passing hole 77 formed in the upper lid 75 of the negativepressure chamber 73 is provided with a negative pressure elbows 78configured to connect the negative pressure chamber 73 and an air-gassuction device (a suction device) 79. The four negative pressure elbows78 are provided at intervals of 90° as illustrated in FIG. 2 and FIG. 3.

In FIG. 5 and FIG. 6, the nitrogen feed pipes 51 and the nitrogen feedpipes 61 penetrate through the negative pressure chamber 73 formed onthe outer periphery of the guide cylinder 18. The nitrogen feed pipes 51for a bottom part is configured to be used when feeding nitrogen gas tothe bottom of the storage bag S, while nitrogen feed pipes 61 for anupper part configured to be used when supplying nitrogen gas to theupper part of the storage bag S.

The nitrogen feed pipes 51 for the bottom part is formed into a straightshape and is supported by the upper lid 75 and the lower lid 76.

The nitrogen feed pipes 61 for the upper part are each formed into anL-shape with a distal end portion thereof directed outward, and aresupported by the upper lid 75 and the outer peripheral cylinder 74. Thenitrogen feed pipes 51 for the bottom part are connected to the nitrogengas feeding apparatus 27 by the elbows 52 provided on upper portions ofthe nitrogen feed pipes 51 for the bottom part. The nitrogen feed pipes61 for the upper part are also connected to the nitrogen gas feedingapparatus 27 via the elbows 62 provided on upper portions of thenitrogen feed pipes 61 for the upper part and nitrogen feed pipes, whichare not illustrated. As illustrated in FIG. 3, a pair of the nitrogenfeed pipes 51 for the bottom part and a pair of the nitrogen feed pipes61 for the upper part are arranged alternately at a 90° interval.Therefore, in FIG. 2, eight elbows 52, 78, 62, 78, 52, 78, 62, 78 areprovided at regular intervals in the circumferential direction on theupper lid 75 of the negative pressure chamber 73.

An action of the powder or granular material feeding apparatus 11 of thefirst embodiment will be described.

In FIG. 7, the powder or granular material feeding apparatus 11 and thestorage bag S are configured to be moved upward and downward withrespect to each other, and when at least one of those is moved upwardand downward, the powder or granular material discharge port 18 a of theguide cylinder 18 enters the storage bag S that stores the powder orgranular material therein. Then, a motor for rotating the auger 19,which is not illustrated, the nitrogen gas feeding apparatus 27 and theair-gas suction device 79 start activating.

The nitrogen gas feeding apparatus 27 ejects nitrogen gas from thenitrogen ejection ports 26 into the guide cylinder 18 through thenitrogen feed pipe 24, the elbow 25, and the nitrogen feed channel 23.Also, the air-gas suction device 79 sucks air in the guide cylinder bybringing the interior of the negative pressure chamber 73 into a lowpressure (negative pressure) with respect to the atmospheric pressurethrough the negative pressure elbows 78.

Subsequently, the auger 19 is rotated by the motor, which is notillustrated, and conveys the powder or granular material from the hopper17 to the powder or granular material discharge port 18 a in the guidecylinder 18 by the blade 22. During this operation, the nitrogen gasfeeding apparatus 27 ejects the nitrogen gas from the nitrogen ejectionports 26 so that the powder or granular material contains the nitrogengas. In this case, the nitrogen ejection ports 26 are formed in therevolving shaft 21 of the auger 19, and hence the nitrogen gas isejected outward from the center of the powder or granular materialconveyed in the guide cylinder 18.

The negative pressure chamber 73 is kept at a negative pressure, andhence sucks the powder or granular material. However the powder orgranular material is prevented from being sucked by the filter 29.Therefore, the negative pressure chamber 73 sucks the air contained inthe powder or granular material via the air-gas suction holes 28, thefilter 29, and the air-gas suction holes 72. At this time, the air-gassuction device 79 sucks the powder or granular material from theperiphery of the guide cylinder 18, and hence the nitrogen gas ejectedfrom the nitrogen ejection ports 26 to the center of the powder orgranular material may be sucked to a portion near the inner periphery ofthe guide cylinder 18, whereby the nitrogen gas may be delivered overthe entire powder or granular material. At this time, the nitrogen gasis taken out with the air to some extent. The amount of the nitrogen gasto be ejected from the nitrogen ejection ports 26 is larger than theamount of the air contained in the powder or granular material.Therefore, the nitrogen gas is delivered to the entire powder orgranular material by pushing the air out from the powder or granularmaterial.

The reason why the air-gas suction device 79 sucks the nitrogen gas tosome extent together with the air contained in the powder or granularmaterial is just for aiding the nitrogen gas to be delivered over theentire powder or granular material, and not for sucking out the nitrogengas entirely to remove the same. The filter 29 used here is configurednot to be clogged easily by the powder or granular material.

As described above, the powder or granular material feeding apparatus 11causes the powder or granular material to contain the inert gas from thenitrogen ejection ports 26 of the gas guide channel 23 outward from theinside of the powder or granular material while conveying the powder orgranular material in the guide cylinder by the auger 19, and sucks thegas in the interior of the guide cylinder by the air-gas suction device79 via the air-gas suction holes 28 and the filter 29 to the outside, sothat the nitrogen gas may be filled within the powder or granularmaterial to prevent oxidization, solidification, and the like of thepowder or granular material and maintain the quality of the powder orgranular material constant for a long term.

In addition, the revolving shaft 21 of the auger 19 includes a pluralityof the nitrogen ejection ports 26 along the axial direction of therevolving shaft 21, and the guide cylinder 18 includes a plurality ofthe air-gas suction holes 28 along the axial direction so as to face theplurality of the nitrogen ejection ports 26. Therefore, the powder orgranular material feeding apparatus 11 may perform the deaeration of thepowder or granular material and filling of nitrogen gas simultaneouslyand efficiently.

Furthermore, the revolving shaft 21 of the auger 19 includes theplurality of the nitrogen ejection ports 26 over the entire length ofthe revolving shaft 21 in the axial direction, and the guide cylinder 18includes the plurality of the air-gas suction holes 28 over the entirelength of the guide cylinder 18. Therefore, the powder or granularmaterial feeding apparatus 11 may perform the deaeration of the powderor granular material and filling of nitrogen gas simultaneously andefficiently even though the speed of conveyance of the powder orgranular material is increased.

In FIG. 7, at least one of the powder or granular material feedingapparatus 11 and the storage bag S is moved upward and downward, and thepowder or granular material discharge port 18 a of the guide cylinder 18enters the storage bag S that stores the powder or granular materialtherein. Then, the nitrogen gas ejects from a gas ejection port 51 a ofthe nitrogen feed pipes 51 for the bottom part into the interior of thestorage bag S. The powder or granular material having the nitrogen gasdistributed over the entire part thereof is supplied from the powder orgranular material discharge port 18 a of the guide cylinder 18 into thestorage bag S filled with the nitrogen gas.

Subsequently, as illustrated in FIG. 8, as a powder or granular materialP is supplied to the storage bag S, at least one of the powder orgranular material feeding apparatus 11 and the storage bag S is movedupward and downward, and the powder or granular material discharge port18 a of the guide cylinder 18 moves in the direction leaving the storagebag S. During this period, the ejection of the nitrogen gas N₂ from thegas ejection port 51 a is stopped. However, the ejection may becontinued.

As illustrated in FIG. 9, when the storage bag is substantially filledwith the powder or granular material P, the nitrogen gas N₂ is ejectedfrom the gas ejection port 61 a positioned at a portion where the powderor granular material discharge port 18 a of the guide cylinder 18 isformed. A gas ejection port 61 a is a lower end portion of the nitrogenfeed pipes 61 for the upper part, and is bent into an L-shape in thedirection away from the guide cylinder 18. The gas ejection port 61 a isbent into the L-shape for the reason of preventing nitrogen gas to befed from the nitrogen gas feeding apparatus 27 through the nitrogensupply elbows 62 for the upper part and the nitrogen feed pipes 61 forthe upper part from hitting against the powder or granular material andhence causes the powder or granular material to be stirred up.

Finally, the upper portion of the storage bag S is closed by a sealingdevice, which is not illustrated, so that the storage bag S is sealed.

In this manner, the interior of the storage bag is in a state of beingreduced in air and, instead, filled with the inert gas in the storagebag. Therefore, the powder or granular material feeding apparatus 11 isconfigured to feed the powder or granular material, having nitrogen gasdistributed over the entire part thereof, to the storage bag that isfilled with nitrogen gas while performing deaeration so that the storagebag can be closed with nitrogen gas filled in an upper portion thereof.

Therefore, since the powder or granular material feeding apparatus 11 isconfigured to reduce the air in the storage bag and, instead, fill thestorage bag with the inert gas, the powder or granular material may befilled with nitrogen gas, alteration, solidification, oxidization, andthe like of the powder or granular material packed into a bag areprevented, and the quality of the powder or granular material may bemaintained constantly for a long term.

In the description given above, the nitrogen gas is ejected from two ofthe nitrogen feed pipes 51 for the bottom part into the storage bag S.However, a configuration in which one of the nitrogen feed pipes 51 forthe bottom part is connected to the air-gas suction device 79, andnitrogen gas is fed to the storage bag from the other nitrogen feed pipe51 for the bottom part after or while air in the storage bag is suckedby the corresponding nitrogen feed pipe 51 for the bottom part is alsoapplicable.

Alternatively, a configuration in which at least one of the nitrogenfeed pipes 51 for the bottom part is configured to be selectivelyconnectable to the nitrogen gas feeding apparatus or the air-gas suctiondevice 79, the air in the storage bag is sucked by the air-gas suctiondevice at first, and then nitrogen gas is supplied to the storage bag byusing the nitrogen gas feeding apparatus is also applicable. In thiscase, if only one of the nitrogen feed pipes 51 for the bottom part isconfigured to be selectively connectable with the nitrogen gas feedingapparatus 27 or the air-gas suction device 79, the other nitrogen feedpipe for the bottom part feeds nitrogen by the nitrogen gas feedingapparatus 27.

(Powder or Granular Material Feeding Apparatus of Second Embodiment)

In FIG. 10 to FIG. 16, a powder or granular material feeding apparatus111 of a second embodiment is also an apparatus configured to feed orfill the powder or granular material into a storage bag K. The powder orgranular material feeding apparatus 111 of the second embodiment has thestructure with some part being the same as that of the powder orgranular material feeding apparatus 11 of the first embodiment.Therefore, parts different from the powder or granular material feedingapparatus 11 of the first embodiment will be mainly described, and thesame parts will be denoted by the same reference numerals with thosedescriptions being omitted.

As illustrated in FIG. 10, a guide cylinder 118 is formed into acylindrical shape, and is configured to guide the powder or granularmaterial, being conveyed by an auger 119 from the hopper 17 to thestorage bag S. The auger 119 includes a revolving shaft 121 positionedin the guide cylinder 118 to rotate, and a blade 122 provided on therevolving shaft 121 to convey the powder or granular material by rotatedby the rotation of the revolving shaft 121 in the guide cylinder 118.The revolving shaft 121 is rotatably supported by the hopper 17 and thecover 20. The revolving shaft 121 penetrates through the cover 20 andthe hopper 17, and extends to a position near a powder or granularmaterial discharge port 118 a of the guide cylinder 118.

A nitrogen feed channel (a gas guide channel) 123 configured to guidenitrogen gas (inert gas) supplied by a nitrogen gas feeding apparatus (agas feed unit) 27 is formed along an axial center of the revolving shaft121 from an upper end to near a lower end of the revolving shaft 121.The nitrogen feed channel 123 includes nitrogen ejection ports (gassupply ports) 126 formed radially outward from the nitrogen feed channel123 as illustrated in FIG. 12. Nitrogen ejection ports 126 areconfigured to allow nitrogen gas, being guided by the nitrogen feedchannel 123, to be ejected out to cause the powder or granular materialto contain the nitrogen gas. As illustrated in FIG. 10, the head portionof the revolving shaft 121 is connected to the nitrogen gas feedingapparatus (the feed unit) 27 configured to feed the nitrogen gas via arotatable elbow 25 and a nitrogen feed pipe 24.

In FIG. 13, a non-hole portion 118 b on which no through hole is formedis provided on the guide cylinder 118 at a midsection of the guidecylinder 118 in the axial direction so as to oppose the nitrogenejection port 126 in the nitrogen supply channel 123. The non-holeportion 118 b corresponds to a cylindrical non-leak cylinder portion (agas non-leak portion) 131. The non-leak cylinder portion 131 is formedso as to avoid the formation of the gap to prevent nitrogen gas fromleaking outward. A protecting cylinder 139 configured to protectrespective pipes, which will be described later, disposed along an outerperiphery of the non-leak cylinder portion 131 on the outer periphery ofthe non-leak cylinder portion 131. A plurality of the nitrogen ejectionports 126 may be formed in the region of the non-leak cylinder portion131 also along the axial direction of the revolving shaft 121.

In FIG. 13, the guide cylinder 118 includes a deaeration portion (anupper sucking portion) 132 on an upstream side of the non-leak cylinderportion 131 in the axial direction (direction of convey of the powder orgranular material) for performing deaeration of the powder or granularmaterial conveyed by the auger 119. The deaeration portion 132 includesan upper porous portion 118 c of the guide cylinder 118 provided with aplurality of deaeration holes (through holes) 135 formed therethrough, acylindrical filter 133 provided on an outer periphery of the upperporous portion 118 c, and a cylindrical upper outer peripheral cylinder134 provided on the guide cylinder 118 so as to separate from the filterand cover the filter 133. The upper outer peripheral cylinder 134 isprovided on the guide cylinder 118 by a ring-shaped upper lid 175 and abottom lid 180. The deaeration holes 135 are configured to guide the aircontained in the powder or granular material in the interior of theguide cylinder 118 to the outside. The filter 133 is configured to allowair contained in the powder or granular material in the guide cylinderto flow outward through the deaeration holes 135, and prevents thepowder or granular material in the guide cylinder from leaking out fromthe deaeration holes 135.

The upper outer peripheral cylinder 134 forms an upper negative pressurechamber 136 for expelling the air in the interior of the guide cylinder118 by a ring-shaped upper lid 175 provided on an upper end thereof, anda ring-shaped bottom lid 180 provided at a lower end thereof. The upperporous portion 118 c having the deaeration holes 135 formed through theguide cylinder 118 is lower in strength. Therefore, the upper outerperipheral cylinder 134 also serves to reinforce the guide cylinder 118.FIG. 13B is a drawing illustrating a positional relationship of theguide cylinder 118, the filter 133, and the upper outer peripheralcylinder 134. When the guide cylinder 118 is hardly reinforced by theupper outer peripheral cylinder 134, a reinforcing cylinder having aplurality of holes formed therethrough in the same manner as thereinforcing cylinder 71 illustrated in FIGS. 4A and 4B of the firstembodiment may be provided on an outer periphery of the filter 133.

An air through hole 138 formed in the upper lid 175 of the uppernegative pressure chamber 136 is provided with a deaeration elbows 137configured to connect the upper negative pressure chamber 136 and anair-gas suction device 79. The two deaeration elbows 137 are provided atintervals of 180° as illustrated in FIG. 11 and FIG. 12.

In FIG. 14, the guide cylinder 118 includes a nitrogen sucking portion(a lower sucking portion) 140 configured to suck residual air remainingin the powder or granular material and nitrogen gas filled in the powderor granular material in the non-leak cylinder portion 131 without beingsucked by the deaeration portion 132 on the downstream side of thenon-leak cylinder portion 131 in the direction of convey of the powderor granular material. The nitrogen sucking portion 140 includes a lowerporous portion 118 d of the guide cylinder 118 provided with a pluralityof nitrogen sucking holes (through hole) 145 formed therethrough, acylindrical filter 143 provided on an outer periphery of the lowerporous portion 118 d, and a cylindrical lower outer peripheral cylinder144 provided on the guide cylinder 118 so as to separate from the filterand cover the filter 143. The lower outer peripheral cylinder 144 isprovided on the guide cylinder 118 by a ring-shaped head lid 185 and alower lid 176. The nitrogen suction hole 145 is configured to guide theresidual air and nitrogen gas contained in the powder or granularmaterial in the guide cylinder 118 to the outside. The filter 143 allowsthe residual air and the nitrogen gas from flowing to the outside viathe nitrogen suction hole 145, and to prevent the powder or granularmaterial in the guide cylinder from leaking from the nitrogen suctionhole 145 to the outside.

The lower outer peripheral cylinder 144 forms an lower negative pressurechamber 146 for expelling the residual air and the nitrogen gas in theinterior of the guide cylinder 118 by the ring-shaped head lid 185provided on an upper end thereof, and the ring-shaped lower lid 176provided at a lower end thereof. The lower porous portion 118 d of theguide cylinder 118 in which the nitrogen suction holes 145 are formed islower in strength. Therefore, the lower outer peripheral cylinder 144also serves to reinforce the guide cylinder 118. FIG. 14B is a drawingillustrating a positional relationship of the guide cylinder 118, thefilter 143, and the lower outer peripheral cylinder 144. When the guidecylinder 118 can hardly be reinforced by the lower outer peripheralcylinder 144, a reinforcing cylinder having a plurality of holes formedtherethrough, which is the same as the reinforcing cylinder 71illustrated in FIGS. 4A and 4B of the first embodiment may be providedon an outer periphery of the filter 133.

The air through hole 148 formed in the head lid 185 of the lowernegative pressure chamber 146 is provided with a lower end of thenitrogen suction pipe 141 that connects the lower negative pressurechamber 146 and the air-gas suction device 79. An upper end of thenitrogen suction pipe 141 penetrates through the upper lid 175, and isconnected to the air-gas suction device 79 via a nitrogen suction elbow142. The two deaeration elbows 137 are provided at intervals of 180° asillustrated in FIG. 11 and FIG. 12.

As illustrated in FIG. 15 and FIG. 16, the powder or granular materialfeeding apparatus 111 of the second embodiment is also provided with apair of the nitrogen feed pipes 51 for the bottom part, and a pair ofthe nitrogen feed pipes 61 for the upper part in the same manner as thepowder or granular material feeding apparatus of the first embodiment.The description of this part will be omitted.

In FIG. 11, the upper lid 175 is provided with eight elbows 52, 137, 62,142, 52, 137, 62, 142 at regular intervals in the circular direction.

The upper outer peripheral cylinder 134, the protecting cylinder 139,and the lower outer peripheral cylinder 144 described thus far may beone integrated cylindrical member.

An action of the second powder or granular material feeding apparatus111 will be described.

In the same manner as illustrated in FIG. 7, the powder or granularmaterial feeding apparatus 111 and the storage bag K are configured tobe movable with respect to each other, and when at least one of those ismoved upward and downward, a powder or granular material discharge port118 a of the guide cylinder 118 enters the storage bag K that stores thepowder or granular material therein. Then, a motor, which is notillustrated, for rotating the auger, the nitrogen gas feeding apparatus27 and the air-gas suction device 79 start activating.

Then, nitrogen gas N₂ is ejected from a gas ejection ports 51 apositioned at positions where the powder or granular material dischargeport 118 a of the guide cylinder 118 is formed. The gas ejection ports51 a are located at lower ends of the nitrogen feed pipes 51 for thebottom part, and eject nitrogen gas that is fed from the nitrogen gasfeeding apparatus through the nitrogen feed elbows 52 and the nitrogenfeed pipes 51 for the bottom part.

When nitrogen gas is ejected from the gas ejection port 51 a, airaccumulated in the storage bag K is replaced by nitrogen gas. When themotor, which is not illustrated, rotates and hence the auger 119rotates, the powder or granular material is transported in the guidecylinder 118 by the blade 122 of the auger 119.

In the interior of the upper negative pressure chamber 136 of thedeaeration portion 132 is kept at a low pressure (negative pressure)with respect to the atmospheric pressure by an activation of the air-gassuction device 79. In this state, in FIG. 13, air contained in thepowder or granular material that reaches the deaeration portion 132passes through the deaeration holes 135 and the filter 133 to be suckedinto the upper negative pressure chamber 136, and further passes throughthe air through hole 138 and the deaeration elbow 137 to be sucked bythe air-gas suction device 79. Consequently, deaeration (degassing) ofair are contained in the powder or granular material passing through thedeaeration portion 132. The filter 133 used here is configured not to beclogged easily by the powder or granular material.

Nitrogen gas supplied by the nitrogen gas feeding apparatus 27 isejected from a nitrogen ejection ports 126 into the non-leak cylinderportion 131 through a nitrogen feed pipe 24 (FIG. 10), the elbow 25 andthe nitrogen feed channel 123 (FIG. 14). Therefore, nitrogen gas isdistributed over the entire powder or granular material reaching theinterior of the non-leak cylinder portion 131. In addition, deaerationof the powder or granular material is performed in the non-leak cylinderportion 131 and is rather in the negative pressure state. Therefore, thenitrogen gas is easily distributed over the entire part of the powder orgranular material. Since the nitrogen gas is ejected radially from thenitrogen ejection ports 126 of the revolving shaft 121 at a center ofthe powder or granular material, the nitrogen gas is distributed overthe entire part of the powder or granular material. Furthermore, sincethe non-leak cylinder portion 131 is formed so as not have a gap, thenitrogen gas is congested (filled) into the powder or granular materialso as to be pushed into the powder or granular material.

Although the nitrogen ejection ports 126 are positioned at a center ofthe non-leak cylinder portion 131 in the axial direction (the directionof convey of the powder or granular material), a plurality of thenitrogen ejection ports 126 may be formed in the thrust direction of therevolving shaft 121. However, if the nitrogen ejection ports 126 areformed at positions too much closer to the deaeration portion 132 andthe nitrogen sucking portion 140, since the nitrogen gas is sucked anddischarged from the deaeration portion 132 and the nitrogen suckingportion 140, the nitrogen gas cannot be used efficiently. Accordingly,it is preferable to form the nitrogen ejection ports 126 at positionswhere the nitrogen gas is distributed to the powder or granularmaterial, being located in the interior of the non-leak cylinder portion131, by utilizing suction force of nitrogen gas that is sucked by thedeaeration portion 132 and the nitrogen sucking portion 140.

In FIG. 14, the powder or granular material filled with the nitrogen gasin the non-leak cylinder portion 131 is fed to the nitrogen suckingportion 140. Nitrogen gas is sucked from the powder or granular materialfed to the nitrogen sucking portion 140 by the air-gas suction device 79so that the nitrogen gas filled in the non-leak cylinder portion 131 isreliably delivered to the entire part of the powder or granularmaterial. The nitrogen gas passes through the nitrogen suction hole 145and the filter 143 to be sucked into the lower negative pressure chamber146, and then passes through the nitrogen suction pipe 141 and thenitrogen suction elbow 142 to be sucked by the air-gas suction device79. At this time, air remaining in the powder or granular material isalso sucked.

The nitrogen sucking portion 140 is not provided for sucking thenitrogen gas contained in the powder or granular material, but forcausing the nitrogen gas to be distributed over the entire part of thepowder or granular material by sucking the filled nitrogen gas from thecenter of the powder or granular material in the non-leak cylinderportion 131 from the outer periphery of the powder or granular material(the inner periphery of the guide cylinder 118). Therefore, the powderor granular material passing through the nitrogen sucking portion 140has the nitrogen gas distributed over the entire part thereof. Thefilter 143 used here is configured not to be clogged easily by thepowder or granular material.

The powder or granular material having the nitrogen gas distributed overthe entire part thereof is fed to the storage bag K filled with nitrogengas from the powder or granular material discharge port 118 a of theguide cylinder 118.

In the same manner as the configuration illustrated in FIG. 8 of thefirst embodiment, as the powder or granular material P is supplied tothe storage bag, at least one of the powder or granular material feedingapparatus 111 and the storage bag K is moved upward and downward, andthe powder or granular material discharge port 118 a of the guidecylinder 118 moves in the direction leaving the storage bag K. Duringthis period, the ejection of the nitrogen gas N2 from the gas ejectionport 51 a is stopped.

Subsequently, in the same manner as the configuration illustrated inFIG. 9 of the first embodiment, when the storage bag is substantiallyfilled with the powder or granular material P, nitrogen gas N₂ isejected from the gas ejection port 61 a positioned at a position wherethe powder or granular material discharge port 118 a of the guidecylinder 118 is formed. The gas ejection port 61 a is bent into anL-shape. Therefore, a probability that the nitrogen gas hits against thepowder or granular material and causes the same to be stirred up isreduced.

Finally, the upper portion of the storage bag K is closed by a sealingdevice, which is not illustrated, so that the storage bag K is sealed.

In this manner, the powder or granular material feeding apparatus 111 isconfigured to expel the air contained in the powder or granularmaterial, fill the powder or granular material with nitrogen gas anddistribute the nitrogen gas over the entire part of the powder orgranular material, then feed the powder or granular material into thestorage bag filled with the nitrogen gas, fill the upper part of thestorage bag with nitrogen gas, and then close the storage bag.

Therefore, the powder or granular material feeding apparatus 111 iscapable of filling the powder or granular material with an inert gas toprevent alteration and solidification of the powder or granularmaterial, and maintaining the quality of the powder or granular materialpacked into a bag constant for a long term.

It is also applicable to configure the powder or granular materialfeeding apparatus 111 of the second embodiment in the same manner as thepowder or granular material feeding apparatus 11 of the first embodimentsuch that air in the storage bag is sucked by at least one of the twonitrogen feed pipes 51 for the bottom part.

The powder or granular material feeding apparatus 111 of the secondembodiment described thus far is configured to expel air in the powderor granular material by the deaeration portion 132 while transportingthe powder or granular material in the guide cylinder by the auger 119,causes the powder or granular material from the nitrogen ejection ports126 to contain nitrogen gas in the non-leak cylinder portion 131, andsuck residual air and nitrogen gas contained in the powder or granularmaterial by the deaeration portion 132. Therefore, the powder orgranular material is filled with the inert gas and hence a qualityguarantee period of the powder or granular materials may be elongated.

INDUSTRIAL APPLICABILITY

The powder or granular material feeding apparatus of the presentinvention is capable of feeding the powder or granular material and,specifically, is optimum to be used for feeding powder or granularmaterials which are subjected to oxidation, alteration, andsolidification such as flour, non-fat dry milk powder, and tonercontaining magnetic material for copying machines.

REFERENCE SIGNS LIST

P: powder or granular material, S: storage bag, N₂: nitrogen gas (inertgas), 11: powder or granular material feeding apparatus, 17: hopper, 18:guide cylinder, 18 a: powder or granular material discharge port, 19:auger, 21: revolving shaft, 22: blade, 23: nitrogen feed channel (gasguide channel), 26: nitrogen ejection ports (gas feed port), 27:nitrogen gas feeding apparatus (gas feeing unit), 28: air-gas suctionholes (through holes), 29: filter, 79: air-gas suction device (suctiondevice), 51 a: gas ejection port, 61 a: gas ejection port, 111: powderor granular material feeding apparatus, 118: guide cylinder, 118 a:powder or granular material discharge port, 119: auger, 121: revolvingshaft, 122: blade, 123: nitrogen feed channel (gas guide channel), 126:nitrogen ejection port (gas feed port), 131: non-leak cylinder portion(gas non-leak portion), 132: deaeration portion (upper sucking portion),133: filter, 135: deaeration holes (through hole), 140: nitrogen suckingportion (lower sucking portion), 143: filter, 145: nitrogen suctionholes (through holes)

1-8. (canceled)
 9. A powder or granular material feeding apparatuscomprising: a guide cylinder for guiding a powder or granular material,having a plurality of through holes formed thereon through which gas inan interior thereof is guided to an outside; a filter provided on aportion of the guide cylinder where the through holes are formed toallow the gas in the interior of the guide cylinder to flow to theoutside via the through holes while prevent the powder or granularmaterial in the guide cylinder from leaking from the through holes tothe outside; a gas feed unit configured to feed inert gas; an augerincluding a revolving shaft positioned in the guide cylinder andconfigured to rotate, and a blade provided on the revolving shaft andconfigured to transport the powder or granular material by being rotatedby the rotation of the revolving shaft in the guide cylinder, therevolving shaft including a gas guide channel configured to guide theinert gas supplied by the gas feed portion and gas feed ports configuredto allow the inert gas guided by the gas guide channel to ejecttherefrom to cause the powder or granular material to contain the inertgas; and a suction device configured to suck the gas in the guidecylinder to the outside of the guide cylinder via the through holes andthe filter.
 10. The powder or granular material feeding apparatusaccording to claim 9, wherein the revolving shaft includes a pluralityof the gas feed ports along the revolving shaft in the axial direction,and the guide cylinder includes a plurality of the through holes alongthe axial direction so as to oppose the plurality of the gas feed ports.11. The powder or granular material feeding apparatus according to claim10, wherein the revolving shaft includes the plurality of the gas feedports over the entire length of the revolving shaft in the axialdirection; and the guide cylinder includes the plurality of the throughholes formed over the entire length of the guide cylinder.
 12. Thepowder or granular material feeding apparatus according to claim 9,wherein the guide cylinder includes: a gas non-leak portion where thethrough holes are not formed and opposing the gas feed ports; an uppersucking portion having the plurality of the through holes formedtherethrough and formed upstream of the gas non-leak portion in theaxial direction; and a lower sucking portion having the plurality of thethrough holes formed therethrough and formed downstream of the gasnon-leak portion in the axial direction.
 13. The powder or granularmaterial feeding apparatus according to claim 10, wherein the guidecylinder includes: a gas non-leak portion where the through holes arenot formed and opposing the gas feed ports; an upper sucking portionhaving the plurality of the through holes formed therethrough and formedupstream of the gas non-leak portion in the axial direction; and a lowersucking portion having the plurality of the through holes formedtherethrough and formed downstream of the gas non-leak portion in theaxial direction.
 14. The powder or granular material feeding apparatusaccording to claim 9, wherein the guide cylinder includes a gas ejectionport configured to eject the inert gas at a distal end thereof.
 15. Thepowder or granular material feeding apparatus according to claim 9,wherein the inert gas is nitrogen gas.
 16. The powder or granularmaterial feeding apparatus according to claim 9, wherein the powder orgranular material is grain powder.
 17. The powder or granular materialfeeding apparatus according to claim 9, wherein the powder or granularmaterial is toner for image formation.